Belt buckle



FIG. 1 is a front elevational view of a belt buckle illustrating my new design;

FIG. 2 is a top-plan view, the bottom plan view being a mirror image thereof;

FIG. 3 is a rear view thereof; and

FIG. 4 is an exploded perspective view thereof. 

The ornamental design for a belt buckle, substantially as shown and described. 